Revolution counting apparatus



Mam}! 138. L. F. UGRESETT REVOLUTION COUNT ING APPARATUS 3 Sheets-Sheetl Affoxwegm Filed Dec. 3, 1955 REVOLUTION COUNTING APPARATUS Filed Dec.5, 1935 5 Sheets-Sheet 2 3D Me Patented Mar. 29, 1938 UNITED STATESPATENT OFFICE REVOLUTION COUNTING APPARATUS Application December 3,1935, Serial No. 52,648

4 Claims.

This invention relates to improvements in revolution-counting apparatus.

One object of this invention is to provide improved revolution-countingapparatus in which an interval-timer and a revolution-counter are bothunder a single control.

Another object of this invention is to provide an improvedrevolution-counting apparatus in which an interval-timer and arevolution-counter are both under a single control and in which therevolution-counter drives a tachometer.

Another object of this invention is to provide an improvedrevolution-counting apparatus formed of rugged elements readilymanufactured and readily assembled to produce a durable efficientconstruction.

With the above and other objects in view, this invention includes allimprovements over the prior art which are disclosed in this application.

In the accompanying drawings, in which one Way of carrying out theinvention is shown for illustrative purposes:

Fig. 1 is a bottom plan View illustrating the chassis of one embodimentof the improved revolution-counting apparatus with the electric wiringillustrated diagrammatically;

Fig. 2 is a front elevation of the chassis;

Fig. 3 is .a rear elevation of the left-hand portion of the chassis;

0 Fig. 4 is an enlarged front elevation of the revolution-counter orcentral unit, with the front panel, dial, and most of the parts mountedforward of the front movement-plate omitted; and

Fig. 5 is a sectional view of part of Fig. 4 on line 5-5 thereof.

In the description and claims, the Various parts are identified byspecific names for convenience, but they are intended to be as genericin their application as the prior art will permit.

Referring to the drawings, the improved revolution-counting apparatusincludes three main units I0, I l and I2, mounted on a panel ormounting-plate Ill to form the chassis. The chassis may be mounted inany suitable case. The ceni5 tral unit I!) is a revolution-counter andincludes indicating-means in the form of a dial l3 and pointers l4 and15, a drivable mechanism 16 including a rotary shaft-end l'l adapted tobe connected by means of the slot I l to a rotary member (not shown),the revolutions of which are to be counted, and a clutch consisting of afixed clutch-element l8, and a slidable clutch-element [9 adapted to bemoved into engagement with the fixed clutch-element l8 by means of anelectromagnet 20 electrically controlled by the wires 2| and 22. Theindicating elements l3, I4 and P5 of the revolution-counter, the variousparts and gearing for driving the pointers I 4, IS, the clutchelementsl8 and IS, the electromagnet 20, and the supporting-plates for the saidparts, are substantially identical with corresponding parts fullydescribed in my patent on timing instruments No. 2,069,876 grantedFebruary 9, 1937.

Among certain of the minor differences of the present construction overcorresponding parts in 10 the said patent may be mentioned theclutch-operating fork 23, which in the present construction is in theform of a flat leaf-spring hinged at 24 to the armature 25. 26 is a fiatleaf-spring which may be provided with a pad 2'! of leather or other 15suitable material and adapted to engage against the movableclutch-element l9 when the latter is moved to open position (Fig. 5), toact in con junction with the sheet-metal spring-washer 28 to limit theoverrun of the pointer.

The flat spring 29 (Fig. l) frictionally presses against the side of thegear 30 to produce a constant drag. Shaft 3! is pivotally mounted in themovement-plates 32 and 33 and has an arm 34 carrying a roller 35 adaptedto press against the heart-shaped resetting-cam 36 to reset the pointerl5 secured to the sleeve 31, which in turn is connected to theheart-shaped cam 36. The shaft 3i also has an arm 38 carrying a roller39 adapted to press against the edge of the resetting-cam 40, whichlatter is fixed to the center-arbor or shaft 4 I, which in turn issecured to the pointer l4, thus providing for resetting the pointer M tozero.

The arm 38 has its outer end pivotally connected to a link 12, which inturn is pivotally connected 35 to the outer end of a lever-arm 43 whichis secured to a shaft 44 pivoted in the movementplates 32 and 33 andcarries at its end a thumblever 45 to permit of manual resetting of thepointers H5 and i5, as described. 40

A spring 48 has its upper end connected to a pin 41 secured to themovement-plate 32 and has its lower end connected in an opening 48 inthe lever-arm 38 to normally hold the lever-arm 38 pulled upwardlyagainst the limit-pin 49 which 5 is fastened to the movement-plate 32.The fixed clutch-element [8 has a gear 56 formed thereon or securedthereto, which gear meshes with a driving-gear 5! secured on a shaft 52mounted in the movement-plates 32 and 33, which shaft 52 extendsrearwardly through the rear movementplate 33 and has secured on its enda bevel-gear 53 which is in driven relationship with a bevelgear 54secured on a shaft 55 mounted for rotation in bearing-brackets 56 and 51secured to 55 the plate 58, which plate 58 is secured to movement-plates32 and 33 by means of pillars 59, 60. The shaft 55 has secured thereto aworm-wheel 6| in driven relation with a worm 62, which is secured to orformed on a shaft 63 mounted in bearings 64 and 65, said shaft 63 beingextended to provide the shaft-end portion I1 and adapted to be connectedby the slot I1 to a rotary member (not shown), the revolutions of whichare to be counted.

A three-legged bracket or brace 66 is secured to the rear of the plate58 and has a supportingbearing 61 for the end-portion ll of the shaft63. The bracket 66 also has an internally-threaded portion 68 adapted tohave engaged therein a corresponding threaded portion of a member such,for example, as a casing of a flexible shaft (not shown), which shaft isto be connected to the shaft-end I1.

Secured to the shaft 63 is a bevel-gear 69 in driving relationship withanother bevel-gear 18, which latter is secured on one end of a shaft IIrotatably mounted in bearings 12 and 13 of a bracket I4 secured to therear face of the plate 58 by screws 15 or any other suitable means. Theshaft I I, on its opposite end, has secured another bevel-gear I6, whichin turn is in driving relation with still another bevel-gear 11, whichin turn is secured on a shaft I8 of a tachometer unit II of one of thewell-known types, such, for example, as the magnetic type illustrated inthe drawings.

The pointer I9 and the dial 89 constitute indicating-means for giving avisual indication of the approximate number of revolutions being made bythe shaft 63 and the end I! thereof at any given instant. Theinterval-timer or time-indicator unit I2 has pointers 8| and 82 and adial 83, in conjunction with clutch-mechanism including fixed andmovable clutch-elements 84, 84, and an electromagnet 85, for actuatingthe clutch-mechanism by electricity supplied through wires 86 and 81. 88constitutes a resetting thumblever. The pointers I5 and 82 arepreferably so geared as to respectively move over one graduation on theinner circles of the dials I3 and 83 for each complete rotation orrevolution of the pointers I4 and BI.

All the parts of unit I2 just described are substantially identical withthe corresponding parts of unit I0, which have been more particularlyhereinbefore set forth and it will, therefore, be unnecessary todescribe this part of the construction of the unit I2 in further detail.The gear 89 formed on the fixed clutch-element 84 is in drivenengagement with a gear 99 driven from the synchronous motor 9I whichreceives its operating current from the wires 92, 93.

In operation, a rotary part such as a flexible shaft having one endconnected to, say, for example, an internal combustion engine (notshown) has its other end connected to the shaftend I1, and the engine isstarted in operation, and has its speed of rotation increased until thepointer I9 of the unit I I indicates a desired speed on the dial 88,say, for example, two thousand revolutions per minute. Wires 92 and 93are connected to a suitable source of electric-current supply such as analternating-current, whereupon since the current is directly fed to thesynchronous alternating-current motor 9I, the latter starts rotating andthrough the gears 99 and 89 rotates the fixed clutch-element 84.

The switch 94 is now closed, thus sending electric current through wires2I, 22 and 86, 81 to the electromagnets 28 and 85, whereupon theelectromagnets simultaneously move the movable clutch-elements I9 and 84into clutching engagement with the fixed clutch-elements I8 and 84, tothus start the pointers of the units I8 and I2 in operation, the elementI8 indicating the actual number of revolutions made by the shaftend I1,and the element I2 indicating the corresponding time during which suchrevolutions are made.

After the lapse of any desired length of time such, for example, as aminute, the switch 94 is opened, with the consequence that both of theclutches of the units I8 and I2 are simultaneously thrown open, and thepointers of these units come to a simultaneous stop. It is, therefore, asimple matter to read directly upon the dials I3 and 83 the exact numberof revolutions shown on the dial I3 which have occurred in the intervalof time shown on the dial 83. If the number of revolutions thusaccurately measured is lower than, say, the two thousand revolutions perminute which the pointer I9 indicates roughly, then the finger-levers 45and 88 are pressed down to reset all of the pointers I4, I5, 8I and 82back to their original zero position, and the speed of the engine whichis being measured is then increased to bring the pointer I9 to a pointbeyond the two thousand mark, to a point that is estimated to be thenumber of revolutions desired in the engine, the speed of which is beingmeasured. When the pointer 19 becomes stationary at the desired point,the switch 94 is again closed, whereupon the clutches of the units I andI2 are simultaneously closed and the pointers I4, I and 8|, 82 thereofsimultaneously start their travel about their respective dials.

When a desired lapse of time has occurred, the switch 94 is opened,whereupon the clutches open simultaneously by the action of the springs95, 96 connected to the armatures 25 and 98 of the electromagnets 20 and85, and the number of actual revolutions is counted on the dial I3, andby calculation in connection with the time interval represented on thedial 83, the exact number of revolutions that the engine is making canbe readily determined. When the engine is finally found to be making asufliciently close number of revolutions to that desired, then anyproceedings such as measuring the quantity of gasoline consumed by theengine at the given speed can be found. If desired, the exact number ofactual revolutions made by the engine throughout the entire period ofthe test, together with the exact duration of the same, can bedetermined by having the units I9 and I2 in operation during the periodof test. The switch 94 can be mounted in any desired way, such, forexample, on the end of a two-wire electric cord that can be operated atany distance desired from the apparatus.

The springs 95 and 96 can be adjusted, as more fully explained in mysaid patent, to equalize the underrun and overrun of the pointers, tosecure maximum accuracy.

The invention may be carried out in other specific ways than that hereinset forth without departing from the spirit and essentialcharacteristics of the invention, and the present embodiment is,therefore, to be considered in all respects as illustrative and notrestrictive, and all changes coming within the meaning and equivalencyrange of the appended claims are intended to be embraced therein.

I claim:

1. A revolution-counting apparatus comprising: a revolution-counterincluding indicatingmeans, drivable-means adapted to be connected to arotary member, the revolutions of which are to be counted, and a clutchinterposed between said indicating-means and said drivablemeans; anelectrically-driven stop-timer having indicating-means; and singleelectric controlmeans connected to said counter and said timer andadapted to be actuated to engage the clutch of the counter to start thecounter-indicatingmeans and simultaneously start the stop-timerindicating-means, and adapted to be actuated todisengage the clutch ofthe counter to stop the counter-indicating-means and simultaneously stopthe stop-timer indicating-means.

2. A revolution-counting apparatus comprising: a revolution-counterincluding indicatingmeans, drivable-means adapted to be connected to arotary member, the revolutions of which are to be counted, and a pair ofnormally-unclutched clutch-members interposed between saidindieating-means and said drivable-means with one of said clutch-membersnormally driven by said rotary member just prior to a countingoperation; a stop-timer including indicating-means, a motor, and a pairof normally-unclutched clutch-members interposed between saidindieating-means and said motor with one of said clutch-members normallydriven by said motor just prior to a counting operation; and singlecontrol-means connected to said counter and said timer and adapted to beactuated to simultaneously engage the pairs of clutch members of thecounter and stop-timer to simultaneously start the counter andstop-timer indicatingmeans, and adapted to be actuated to simultaneouslydisengage both said pairs of clutch members to simultaneously stop bothsaid indicatingmeans.

3. A revolution-counting apparatus comprising: a revolution-counterincluding indicatingmeans, drivable-means adapted to be connected to arotary member, the revolutions of which are to be counted, and a pair ofnormally-unclutched clutch-members interposed between saidindicating-means and said drivable-means with one of said clutch-membersnormally driven by said rotary member just prior to a countingoperation; a stop-timer including indicatingmeans, an electric motor,and a pair of normallyunclutched clutch-members interposed between saidindicating-means and said motor with one of said clutch-members normallydriven by said motor just prior to a counting operation; and singleelectric control-means connected to said counter and said timer andadapted to be actuated to simultaneously engage the pairs ofclutchmembers of the counter and stop-timer to simultaneously start thecounter and stop-timer indicating-means, and adapted to be actuated tosimultaneously disengage both said pairs of clutch-members tosimultaneously stop both said indicating-means.

4-. A revolution-counting apparatus comprising: a revolution-counterincluding indicatingmeans, drivable-means adapted to be connected to arotary member the revolutions of which are to be counted, a pair ofclutch-members interposed between said indicating-means and saiddrivablemeans with one of said clutch-members normally driven by saidrotary member just prior to a counting operation, yieldable-meansadapted to normally yieldably hold said clutch-nembers in unclutchedrelation, and electromagneticmeans adapted to clutch said clutch-memberstogether; a stop-timer including indicatingmeans, an electric motor, apair of clutch-members interposed between said indicating-means and saidmotor with one of said clutch-members normally driven by said motor justprior to a counting operation, yield-able-means adapted to normallyyieldably hold said clutch-members in unclutched relation, andelectromagnetic-means adapted to clutch said clutch-members together;and single electric control-means connected to the electromagnetic-meansof said counter and said stop-timer and adapted to be actuated tosimultaneously engage the pairs of clutch-members of the counter andstop-timer to simultaneously start the counter and stop-timerindicating-means, and adapted to be actuated to simultaneously disengageboth said pairs of clutchmembers to simultaneously stop both saidindicating-rneans.

LEONARD P. DORSETT.

